End mills types include ball, square and corner radius, with the subject matter of the present application relating to the latter type.
A corner radius end mill is normally formed with an end gash, and, to prevent unacceptable discontinuities, can be formed with a so-called blended gash.
Example end mills publications disclosing blended gashes are disclosed in National Aerospace Standard 986 (1973; sheet no. 55), and US 2011/0217132.